Effect of Platelet-Activating Factor and PAF-Antagonist on the Mucociliary Clearance of the Eustachian Tube in Guinea Pigs

Rhee, Chung Ku

Abstract

BACKGROUND AND OBJECTIVES: The purpose of this study was to test whether platelet activating factor (PAF) impairs the mucociliary clearance function of the eustachian tube (ET)in dose dependent manner and PAF-antagonist can prevent the impairment of mucociliary function of the ET induced by PAF.
RESULTS
Coomassie Brilliant Blue (CBB) dye transport time (DTT) in normal guinea pigs was 69 seconds. The dye transport time after the applications of normal saline, PAF 1, and 2 ug/ml of PAF into the bullae were 66, 74, and 157 seconds, respectively. The time was over 15 minutes when 4, 8, and 16 ug/ml of PAF were applied. The DTT were 62 seconds when the animals were pretreated with PAF-antagonist (WEB 2170). There were significant delay in the DTTs after treatment with 2, 4, 8, and 16 ug/ml of PAF. Histopathological examination of ETs from groups with significant delay in DTTs showed intact cilia, mucus plugs, increased inflammatory cells, and exfoliation of cells.
CONCLUSION
This study demonstrated that PAF impaired mucociliary clearance function of the eustachian tube in dosedependent manner. This impairment of mucociliary clearance function was prevented by pre-treatment with PAF-antagonist. The findings of this study suggest that PAF plays an important role in the pathogenesis of otitis media by impairing eustachian tube clearance function.